Conifers make excellent screens or hedges, but they can be difficult to tell apart
Taxus baccata (yew)
Shoots have two ranks of dark green leaves with lighter green undersides carried along the stem. Females have bright red fruits. A traditional choice for hedging and topiary, yew can be confused with young plants of Sequoia sempervirens (coast redwood), but this has white bands on the leaf undersides and is relatively uncommon. The Irish yew T. baccata ‘Fastigiata’ AGM has leaves in whorls around the stem and an upright habit. Yew is poisonous so should not be planted close to livestock.
xCupressocyparis leylandii (Leyland cypress)
This is a vigorous hybrid between Cupressus macrocarpa and Chamaecyparis nootkatensis that needs cutting regularly. The foliage forms flat sprays with scale-like leaves, similar to those of Chamaecyparis but more elongated and fleshier. Citrus scented when crushed. Gold ‘Castlewellan’ is popular.
Chamaecyparis lawsoniana (Lawson’s or false cypress)
This forms a conical tree with flat, scale-like leaves like Leyland cypress but in denser, drooping sprays with a resinous, musty smell. Distinctive small, red, male cones are often borne in profusion around March; female cones are round and about 7mm across. There are a great number of cultivars some with soft, needle-like juvenile foliage. Dark ‘Green Hedger’ AGM and gold ‘Stewartii’ are recommended for hedging.
Thuja plicata (western red cedar)
This is fast growing with flat sprays of glossy, scale-like leaves, broader than those of Lawson’s cypress. These smell strongly fruity if crushed, like pineapple or fruit pastilles. Female cones are flask-shaped, to about 10mm long. The cultivar ‘Atrovirens’ is the clone most frequently offered and makes a thick hedge. Needs fertile, moisture-rich soils.
Cupressus macrocarpa (Monterey cypress)
This has a columnar habit when young but becoming broadly spreading with age. The dense, scale-like foliage is arranged in sprays around the branches, not in flattened sprays. Leaves have strong lemon scent when crushed. The cones are woody, to about 3cm across. ‘Goldcrest’ AGM is a good golden cultivar with an upright habit and feathery, juvenile foliage. Monterey cypress is best used as an informal screen. It is salt tolerant so suited to coastal gardens, but is not reliably hardy in colder areas.
James Armitage
Further information
Conifer hedges: pruning & trimming